Instantly find explanations, causes, and resolution steps for every Claim Adjustment Reason Code (CARC) and Remark Code.
Claim Adjustment Reason Codes (CARC) explain why a payment differs from what was billed. Every 835 ERA and EOB uses these standardized codes.
Search any code or keyword above. Each page includes the full description, common causes, resolution steps, and appeal guidance.
Each denial code page also links to a dedicated Remark Code page — optimized for providers searching for ERA remark code context.
Most denials are reversible. Our guides walk you through the correct steps to correct, resubmit, or formally appeal each denial type.
| Code | Description | View |
|---|---|---|
| 1212 | C Pend 4 The Requested Itemized Bill was not received in the allotted timeframe. | Details → |
| 1213 | C Pend 5 The Requested Referral or Authorization was not received in the allotted tim… | Details → |
| 1214 | C Pend 6 The Requested Medical Documentation was not received in the allotted time fr… | Details → |
| 1215 | Forwarded to Well Med Claim was forwarded to WellMed Call 1 8005507691 to check claim… | Details → |
| 1217 | Missing Charge Missing/Incomplete/Invalid Charges | Details → |
| 1218 | Not Medically Necessary NOT MEDICALLY NECESSARY | Details → |
| 1219 | ICRS DRG Audit iCRS DRG Audit | Details → |
| 1220 | Connolly Recovery Audit Connolly Recovery Audit | Details → |
| 1221 | Reclaim Recovery Audit Reclaim Recovery Audit | Details → |
| 1222 | Clinical Trial Claims CLINICAL TRIAL FILE WITH MEDICARE AND RESUBMIT AS SECONDARY | Details → |
| 1223 | Dual Eligible Acute Services Acute Care Services are billed to the members primary Me… | Details → |
| 1224 | Missing Medical Records We requested medical records that have not been received resu… | Details → |
| 1225 | TX- 2013 Claim Lines | Details → |
| 1226 | 360 Form 360 Form was not received or was incomplete. Please submit Completed/Correct… | Details → |
| 1227 | Mis-directed claim This is a Misdirected Claim/ Service. Submit claim to Cigna LifeSo… | Details → |
| 1229 | Sequestration Reduction in Federal Spending. 2% reduction in payment applied | Details → |
| 1230 | Invalid CPT/HCPC Claim has been submitted with an invalid CPT/HCPC code. Please resub… | Details → |
| 1264 | Service is the responsibility of the IPA. This claim is the responsibility of and wil… | Details → |
| 1282 | Provider is Non-Par - Point of Service benefit app Provider is Non-Par - Point of Ser… | Details → |
| 1302 | Do Not Bill Member. Coordinate benefits with the s Do Not Bill Member. Coordinate ben… | Details → |
| 2013 | Service Line determination and/or payment are being processed separately. Please allo… | Details → |
| 2309 | All claims for participating providers All claims for participating providers must be… | Details → |
| 2310 | Refund This refund was received due to an overpayment. | Details → |
| 2311 | COB Cigna HealthSpring has no liability due to Coordination of Benefits. | Details → |
Medical claim denial codes — formally known as Claim Adjustment Reason Codes (CARC) — are standardized identifiers maintained by the X12 standards body and used across all Medicare, Medicaid, and commercial payer 835 electronic remittance transactions. When a claim is paid at a different amount than billed, at least one CARC code must accompany the remittance advice to indicate the specific reason for the adjustment.
The most frequently encountered codes include CO-16 (missing or invalid claim information), CO-45 (charges exceeding fee schedule), PR-1 (patient deductible), CO-29 (timely filing deadline exceeded), and CO-4 (procedure code inconsistent with modifier). Each represents a distinct, actionable reason that has a defined resolution pathway.